NEET 2013
- Exam
- NEET
- Year
- 2013
- Subject
- Physics
- Chapter
- Work, Power and Energy
NEET 2013 · Physics · Work, Power and Energy
A uniform force of (3 i+j) N acts on a particle of mass 2 ~kg ....
A uniform force of acts on a particle of mass . Hence the particle is displaced from position to position . The work done by the force on the particle is
Options
- A
- B
- C
- D
Correct answer
A.
Step-by-step solution
Given, force \begin{array}{l}
r_1=(2 i+k) m \text{ and } r_2 =(4 i+3 j-k) m \\
\therefore s=r_2-r_1=(4 i+3 j-k)-(2 i+k) \\
=(2 i+3 j-2 k) m \\
\begin{array}{l}
\therefore W=F \cdot s & =(3 i+j) \cdot(2 i+3 j-2 k) \\
& =3 \times 2+3+0 \\
& =6+3=9 \mathrm{ J}
\end{array}\\
\end{array}